Cannot cancel fiber even if you pay in advance and return router

I have been trying to cancel my fiber with Webafrica for a couple of days now. It is not possible..... Paid them a month's notice for June and returned their router this morning. Still cannot get an agent who can assist me to cancel the fiber. Now they want another R999 for a cancellation fee. As i understood from previous chats with them the R999 only applies if the router is not returned. I have however done so but cannot seem to find an agent who can assit me to cancel my fiber. Note I have paid for May and June so I will not be able to make use of the service without the router. Was so desperate to get rid of these people that I was willing to pay for a month and return their router. The games they play are unbelievable and someone should report these guys. They will obviously just keep billing me and act stupid. Please do not even consider doing business with this *********, evil company